[gmx-users] ForceField of ethanol and the default parameters in Gromacs

[ZUO Taisen]

 Dear Gromacs developer:
       
       There is a topology file of ethanol in the OPLS FF of the new version of Gromacs (Gromacs2016 please see bellow). However, I did not see any bond, angle or dihedral parameters. Does this means that Gromacs use the default parameter? 

     If we want to compare this topology with the topology from literature, where should I find these top parameters in Gromacs one by one?

     Is these default parameter accurate enough to simulate polymer like Polyethelene or Polystyrene? 

     Thank you very much!

Sincerely yours,
Taisen Zuo

 ;
; Ethanol, Jorgensen et al. JACS 118 pp. 11225 (1996)
;
[ moleculetype ]
; name  nrexcl
ETH     3

[ atoms ]
;   nr    type   resnr  residu    atom    cgnr        charge          mass
     1       opls_157       1     ETH       C       1   -0.18
     2       opls_156       1     ETH       H       1   0.06
     3       opls_156       1     ETH       H       1   0.06
     4       opls_156       1     ETH       H       1   0.06
     5       opls_157       1     ETH       C       2   0.145
     6       opls_156       1     ETH       H       2   0.06
     7       opls_156       1     ETH       H       2   0.06
     8       opls_154       1     ETH      OA       2   -0.683
     9       opls_155       1     ETH      HO       2   0.418

[ bonds ]
;  ai    aj funct           c0           c1
 1      5       1
 3      1       1
 4      1       1
 2      1       1
 7      5       1
 6      5       1
   8      5       1
 9      8       1

 [ pairs ]
 ; i    j       func
 2      6
 2      7
 2      8
 3      6
 3      7
 3      8
 4      6
 4      7
 4      8
 1      9
 6      9
 7      9
[ angles ]
;  ai    aj    ak funct           c0        c1
; H3
 2      1       5       1
 3      1       5       1
 4      1       5       1
;
 4      1       3       1
 4      1       2       1
;
 3      1       2       1
;
 1      5       7       1
 1      5       6       1
 1      5       8       1
;
 5      8       9       1
;
 6      5       7       1
 6      5       8       1
;
 7      5       8       1
;
[ dihedrals ]
 2      1       5      6        3
 3      1       5      6        3
 4      1       5      6        3
 2      1       5      7        3
 3      1       5      7        3
 4      1       5      7        3
 2      1       5      8        3
 3      1       5      8        3
 4      1       5      8        3
 1      5       8      9        3
 6      5       8      9        3
 7      5       8      9        3


--
Taisen Zuo

China Spallation Neutron Source，Institute of High Energy Physics， Chinese Academy of Science
A1-510, Zhongziyuan road NO.1, Dongguan, Guangdong, PR China. 523770
Tel: 86-0769-89156495
Cell: 13650469795


左太森
中科院高能物理研究所中国散裂中子源
广东省东莞市大朗镇中子源路1号A1-510
邮编：523770 
办公电话：86-0769-89156495
手机：13650469795